Why do so many cultures view the realm of the dead as subterranean--an "underworld" below the ground?

Answer 1

Excellent question! This is a bit of a chicken-egg problem in that it’s difficult to tell whether burial practices (in-ground interment, mummification, cremation, etc) are the result of religious beliefs, or if religious stories were crafted around previously existing burial practices. Many cultures believe in a three-plane existence: the above-realm (usually the realm of deities and great heroes), the middle-realm (where we mortals live), and the below-realm (where the average person or evil-doers, depending on the culture, dwell).

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